code: def test_squash_plots_properties_revs():
      group = [
          ("v3", "config_file", "plot_id", {"foo": 1}),
          ("v2", "config_file", "plot_id", {"foo": 2, "bar": 2}),
          ("v1", "config_file", "plot_id", {"baz": 3}),
      ]
  
      plot_properties = _squash_plots_properties(group)
  
      assert plot_properties == {"foo": 1, "bar": 2, "baz": 3}
  
file_path: dvc/tests/unit/render/test_match.py
imports: import pytest
  from funcy import set_in
  from dvc.render import FIELD, FILENAME, REVISION
  from dvc.render.converter.vega import VegaConverter
  from dvc.render.match import PlotsData, _squash_plots_properties, match_defs_renderers
label_desc: Use image node_id 4 for calling a global function with example usage: test_squash_plots_properties_revs() without return types